Investors will also get their first look at how the economy fared in the first three months of the year when the Bureau of Economic Analysis releases its initial estimate of first quarter U.S. GDP at 8:30 a.m. ET. According to FactSet, the economy is expected to show a 1% annual growth, sharply below the 2.6% growth in the fourth quarter.

"U.S. GDP is expected to show a dramatic slowdown from 2013, but to some extent this news is already baked into current market activity," wrote Chris Beauchamp, market analyst for IG in London. "The key will be the Fed statement, which is expected to underline the FOMC's view that the economy still needs careful nursing to reach full health."

But Energizer(ENR) shares jumped 9% after the battery company announced plans to split into two companies, Household Products and Personal Care.

In other corporate news, CNNMoney parent Time Warner(TWC) reported earnings and sales that topped forecasts, helped by strong revenue from the Lego movie.

Shares of Royal Dutch Shell(RDSA) rose after the oil giant reported better-than-expected quarterly results and hiked its dividend. eBay(EBAY) shares declined a day after the online marketplace reported disappointing earnings.

Takeover talk continues overseas, with shares of French company Alstom(ALSMY) rallying 8% in Europe after General Electric(GE) bid $13.5 billion to take over the firm's power divisions. German firm Siemens(SI) may yet make a counter offer.